背景：
在学生信息管理系统中有的地方需要限制输入的内容。
措施：
限制输入的文本为大小写字母以及数字
Private Sub txtSID_KeyPress(KeyAscii As Integer)
Select Case KeyAscii
Case 8
Case Asc("a") To Asc("z")
Case Asc("0") To Asc("9")
Case Asc("A") To Asc("Z")
Case Else
KeyAscii = 0
End Select
End Sub
限制特殊的字符
Private Sub txtName_KeyPress(KeyAscii As Integer)
If KeyAscii > 0 And Key < 8 Then KeyAscii = 0
If KeyAscii > 8 And Key < 65 Then KeyAscii = 0
If KeyAscii > 90 And Key < 97 Then KeyAscii = 0
If KeyAscii > 122 And Key < 127 Then KeyAscii = 0
Select Case KeyAscii
Case 8
End Select
End Sub说实话，老是觉得这个博客有点水，毕竟是自己的能力不行，所以还请大佬们在评论区补充，我补充进正文区。（sharing is power）！